Floor cramp



April 16, 1940.

R. E.. CHAPMAN ET A1.

FLOOR CRAM? Filed Aug. 9, 1959 1NVENTORS. Roy E. CHAPMAN ATTORNEYS.

Patented Apr. 16, 1940 l PATENT ortica FLOOR oRAMP Roy E. Chapman, CincinnatLand John iCahall, Norwood, Ohio, assignors ,by direct vandmesne assignments, of one-half to wood, Ohio, and one-half to said Cahall Application August 9,

7 Claims.

The invention relates to -oor cramps vfor forcing the joints of floor boards close togetherrprior to the boards being nailed. Itis'the objectof our invention 'to provide an 'improved cramp which 15 .will be positive in its action, which will exert va `very :powerful cramping action and which will 'be-easy Vto manipulate and to move about during use.

It is'specifically the objectof our vinvention to #l -provide a floor oramp exerts a directleverage action-on a gear-segment which actuates a rack bar provided at its end with a crampingfhead.

It is a-.further object'of our invention toprovide a oor cramp wherein the force exertedagainst the edge of the floor boards is slightly downwardly so that any tendency for the application of pressure to result in the floor boards springing up is avoided.

It is .a further object of our invention to prode a iioor cramp wherein cleats for holding the apparatus in position on the underlying floor boards may be adjustable for various types of work.

Broadly it is the object of our invention to provide a oor cramp wherein great leverage may be obtained in an apparatus of simple and readily portable construction, which will greatly facilitate the work of a oor layer.

The above objects and other objects to which reference will be made in the ensuing disclosure, we accomplish by that certain combination and arrangement of parts of which we have illustrated a preferred example.

In the drawing:

. Figure 1 is an end elevation of a preferred type of device, with a portion thereof shown in section, as indicated by the lines I-I in Fig. 2. f

Fig, 2 is a sectional view taken along the lines 40 2 2 of Fig. 1.

Fig. 3 is a head'.

The tool is provided with .a base plate l having threaded openings 2 therein, arranged at spaced 45 intervals wherein cleats 3 having Shanks 4 may be adjustably mounted by means of nuts 5. If it is desired to expand the cleats 3 further the base plate I, this may be accomplished by turning down the threaded Shanks 4 and adjust- 50 ing the nuts 5 in a different position.

A guide plate 6 is provided with a milled slot 'l which as shown in Fig. 2, is inclined downwardly toward the open end of the slot so that the rack bar 8 which has the cramping head 9 pivotally 55 secured thereto as indicated at l0, will have a perspective View of the cramping wherein a ffoot treadle from.

1939, Serial No. 289,250 (Cl. v254-,12)

movement slightly downwardly from horizontal, Aso thatsthe tendency-to cause Vthe oor board to buckle rwhen pressure is applied, is avoided.

lA Ahousing Il has a-boss -l2 with a trunnion bearing I3 for the lfootpressure lever M. The "f5 `lever Hl --has a foot rest plate l5, pivoted thereto as indicated at 16.

Journaled on the -lever M at ll' -we employ a link i8 which isfjournaledas indicated at I9 to a gearsegment 120. --Theteeth 2| of thetgear I"I0 segment engage the teeth `22 y'of the rack bar d.

Thus-it wilLbe-obvious that @downward pressure on fthefoot plateof the lever-'M lcauses thegear segment lto rotate clockwise as #indicated lin Fig. '2, and this causes the rack bar 8 to be 15 advanced to the left as shown in this gure, so that thecramping head Sewill compress the floor board in proper'position for nailing.

A boss 23 is extended from the link I8 and a rod 24 extends from theboss 23, so that a 20 spring 25 which has its lower end bearing against a shoulder 26 in theA housing Il, will be compressed during the actuation of the machine by means of the lever I4. 4

A pawl 2 engages a ratchet segment 28 formed 25 in the periphery of the gear segment 2d .opposite the gear teeth 2|, so that as the cramping head is advanced the pawl 21 holds the gear segment 20 in position.

A pawl releasing bar 30, extends up in a vcylin- 30 drical head 3l secured tothe housing Il, and the rod 30 is secured to one end of a lever bar 32. 'Ihe lever bar is pivoted at 33 somewhat eccentrically so that a pawl release handle 34 may be depressed and cause the elevation of the pawl 35 releasing bar 30.

The operation of the cramping device will be obvious. The apparatus is moved into position for use with a cramping head 9 arranged with its groove 35 engaging the tongue ofthe oo-r 40 board to be cramped into position. The foot treadle l5 is then depressed to a desired extent, the cleats 3 meanwhile holding the apparatus in position. After the floor board has been nailed into position, the pawl release handle 3l# is de- 45 pressed and the cramping head may be released from contact with the flooring board and moved to another position.

Having thus described our invention, what we claim as new and desire to secure by Letters Patent is: f

1. In a floor cramp, a supportng frame, a rack bar slidably mounted in said frame and having a cramping head thereon, a gear segment journaled in said frame having gear vteeth engaging the gear teeth of said rack, an actuating lever pivoted in said frame, a spring tensoned link connected to said lever and to said gear segment eccentric of the journal thereof, and pawl and ratchet means for holding said gear segment in diierent positions of compression of said spring.

2. In a floor cramp, a supporting frame, a rack bar slidably mounted in saidframe and having a cramping head thereon, a gear segment journaled in said frame having gear teeth engaging the gear teeth of said rack, an actuating levei` pivoted in said frame, a spring tensioned link connected to said lever and to said gear segment eccentric of the journal thereof, and pawl and ratchet means for holding said gear segment in different positions of compression of said spring, said cramping head swiveled on a vertical pivot in said rack bar.

3. In a floor cramp, a supporting frame, a rack bar slidably mounted in said frame and having a cramping head thereon, a gear segment journaled in said frame having gear teeth engaging the gear teeth of said rack, an actuating lever pivoted in said frame, a spring tensioned link connected to said lever and to said gear segment eccentric of the journal thereof, and pawl and ratchet means for holding said gear segment in dierent positions of compression of said spring, the slidable mounting for said rack bar comprising a slotted portion extending downwardly at a slight angle to the horizontal.

4. In a oor cramp, a supporting frame, a rack bar slidably mounted in sad frame and having a cramping head thereon, a gear segment journaled in said frame having gear teeth engaging the gear teeth of said rack, an actuating lever pivoted in said frame, a spring tensioned link connected to said lever and to said gear segment eccentric of the journal thereof, and pawl and 5 ratchet means for holding said gear segment in different positions of compression of said spring, and'cleats adjustably mounted in said supporting frame.

5. In a iioor cramp, a slidable rack bar, a gear `segment for actuating said rack bar and an actuating lever having a link connected to said gear segment and eccentric of the journal of said gear segment.

6. In a oor cramp, a slidable rack bar, a gear segment for actuating said rack bar and an actuating lever having a link connected to said gear segment and eccentric of the journal of said gear segment, a compression spring connected to said link and pawl and ratchet means for holding said gear segment in advanced positions of movement.

7. In a floor cramp, a slidable rack bar, a gear segment for actuating said rack bar and an actuating lever having a link connected to said gear segment and eccentric of the journal of said gear segment, a compression spring connected to said link and pawl and ratchet means for holding said gearsegment in advanced positions of movement, and means for releasing said pawl to permit said spring to retract said gear segment. t

ROY E. CHAPMAN. JOI-IN CAHALL. 

